Ring bracing of rigid airships



March 9, 1937. U

RING BRACING OF RIGID AIRSHIPS Filed mi. 3, 1932 .55 ship near its'longitudinal axis.

Patented Mar. 9, 1937 to Luftschiffbau Zeppelin Gese'lls'chaft mit beschrankter Haftung, Friedrichshafen, Germany Application November-3, 1932, Serial o. 640,920

In Germany November 9, 1931 12 Claims.

; My invention relates to rigid airships which are gas-inflated and hasspecial reference to the ring bracing of such ships.

As is wellknown the inner space of rigid-airship bodies-or hulls is subdivided longitudinally into individual compartments by means of bracings which generally serve for staying the socalled ring girders in their plane. lnsome-cases instead .of using light ring girders and staying them by braces, strong girders were made use of which form a substantially circular truss without needing an inner bracing. M-y invention does not relate to this latter kind of construction but to rings of rigid airships with light circumferential girders and inner bracing.

This ring bracing serves .also for supporting the ,gas pressure of the gas .cell inneighbouring compartments, which may vary if the cells are not inflated to the same degree, or if .the airship is longitudinally inclined, or if one gas cell is defia'ted for some reason. The ring'bracing in such cases yields toward the side on which the gas pressure'is 'lower'or has disappeared totally. This yielding will go -as 'far as the expansion of the stays, which may be wires or cables, allows. The -wires and cables as well "as the ring girders in such cases get a super load which makes it necessary to give adequate dimensions to these elements. The greatest load on the ring bracingandthe ring girders 'occurswhen one oftwo afford. This means a considerable additional weight in structural elements.

By my invention I reduce the loads on the 'girders'and stays by providing a special system of stays. The stays coming from the circumc ference of the ring I unite in groups of three or more and lead them to 'two or more :points near thelongitudinalaxis of 'theairship and here I .provide for a connection between these points. "I prefer to make this connection so that the distance betweenthe endpoints -'of thestays near the axis 'of the ship can 'be varied. If the 'distancebetwe'en these pointsis 'increased'thebra'cing elements, if difference of pressure on "both sides thereof exists, will yield toward'the lower pressureside.

I prefer to combine this -'new construction "according "to my invention with the prior known construction of a longitudinal structural element running through the compartments 'of the Elements "of :this kind have beenma'deuse of for'example'in bigger airships having stayed rings, in which at "the same time they served as a catwalk between the gas cellsfthe upper cells containing'support- .50 ing gasgsuch as hydrogen or helium, whereas the lower cells were inflated with a fuel gas for the engines.

By fixing the groups of stays to this longitudinal element .in such (manner that the length of the stays .can :be varied, .as above explained,

I gain the advantage that the'total length of such able or elastic elements ateach ring corner to which the net-work is fastened. This means a considerable number of elastic elements which are comparatively heavy. With my new construction :in connection with stayed rings I need only as many elastic elements as there are groups of stays,'which "maybe two or preferably three. Of courseinpertain cases it may be advisable'to have four-or'more groups. Butgeneral- 1y three of them-will answer'the' purpose.

My new way o'fconstruction means of course saving in weight, which is *of greatest importance in connection with aircraft. Furthermore, a few elastic elements are 'much easierto control and inspect than a great number of them, especially if "they "are situated near -a-gangway -'0r catwalk and not distributed overtheentirecircumference of the ring.

The elements interconnecting the end points of the groups of ring stays or braces c'an be suchas must be operated by hand for their lengthening or shortening; but I prefer to use springs, air bufiers or thelikewhich yildautomatically with the overload {and cause return to the original position whenever theoverload vanishes.

My invention will be understood best when having reference -to=the drawing which'represents sever-a1 examples embodying my invention.

Figs. 1 and 2 are-eachan elevation of an airship ring, but showing two different examples, in a diagrammatical *manner.

Fig. 3 is a partial longitudinalsection through Fig. 6 gives another example of such end connection but in combination with a longitudinal structural element.

Fig. 7 is a third example of this kind.

Between the longitudinal girders I of the airship the ring girders 2 are situated. There are radial braces 3 and auxiliary braces 4 connecting the ring corners with the inner end points 25 near the longitudinal axis of the airship.

In the examples represented there are formed three groups of such stays or braces 3 leading to three end points 25. The elements interconnec ing points 25 and adapted to be shortened or lengthened are turn buckles I l, as shown in Figs. 1, 2, 3, 4, 5, and 7, respectively, or they may be springs or the like, as represented in Fig. 6. In this latter case the spring arrangements (I2, l3, [4, I5) connect all three points 25 to one common middle point 35 which in the present example at the same time is a corner of the longitudinal gang way 5.

In Figs. 3 and 4 the gas cell wall is indicated at I.

In the cases in which turn buckles are used as interconnecting members it is necessary to loosen them to an adequate degree whenever undue superpressure or overload on the ring braces or stays occurs, and to make them tight again when such overload vanishes. If springs or other yieldable elements are made use of no special operation is necessary, but, of course, the springs must be adequately chosen.

If there are only two groups of ring braces leading to two end points it is advisable to provide an upper and a lower group andin case there is a longitudinal structural element-to connectthe lower group to this element directly and to have the yieldable member between the upper group and the longitudinal element so that the upper group of braces can give more way than the lower group which corresponds to the gas pressure distribution. Such construction could easily be obtained if in Fig. 6 the two lower groups of stays ending in members 8 and 9 were united and directly fixed to gang way 5.

I do not want to be limited to the details described or shown in the drawing, as many variations will occur to those skilled in the art.

What I claim is:

1. In an airship comprising a hull having a ring member, a plurality of radially extending braces connected at their outer ends to said ring member, and a resilient means for connecting the inner ends of at least one group of a plurality of said braces with others of said braces at a central location.

2. In an airship comprising a hull having a ring member, a plurality of radially extending braces connected at their outer ends to said ring member, a plurality of elements each connecting the inner ends of separate groups of said braces with one another, and separate means for connecting each of said elements with one another at a central location.

3. In an airship comprising a hull having a ring member, a plurality of radially extending braces connected at their outer ends to said ring member, a plurality of elements each connecting the inner ends of separate groups of said braces with one another and tensioning means for connecting each of said elements with one another at a central location.

4. In an airship comprising a hull having a ring member, a plurality of radially extending braces connected at their outer ends to said ring member, a plurality of elements each connecting the inner ends of separate groups of said braces with one another and yieldable means for connecting each of said elements with one another at a central location.

5. In an airship comprising a hull having a ring member, a substantially axial supporting member, a plurality of radially extending braces connected at their outer ends to said ring memher, a plurality of elements each connecting the inner ends of separate groups of said braces with one another, and adjustable means for connecting each of said elements with one another at a central location.

6. In an airship comprising a hull having a ring member, a substantially axia1 polygonal supporting member, a plurality of radially extending braces connected at their outer ends to said ring member, a plurality of elements each connecting the inner ends of separate groups of said braces with one another, means for connecting each of said elements with different ones of the apexes of said supporting member, and a single adjusting member for each group adapted to simultaneously adjust the tension in all of the braces in that group.

7. In an airship comprising a hull having a ring member, a substantially axial triangular supporting member, a plurality of radially extending braces connected at their outer ends to said ring member, a plurality of elements each connecting the inner ends of separate groups of said braces with one another, means for connecting said elements with different ones of the apexes of said supporting member, and a single adjusting member for each group adapted to simultaneously adjust the tension in all of the braces in that group.

8. In an airship comprising a hull having a ring member, a substantially axia1 triangular supporting member, a plurality of radially extending braces connected at their outer ends to said ring member, a plurality of elements each connecting the inner ends of separate groups of said braces with one another, and means for connecting each of said elements directly with the same apex of said supporting member.

9. In an airship comprising a rigid hull having a ring member requiring inner bracing, inner braces fixedly secured at their outer ends to the ring member, a plurality of spaced plates, the inner ends of said braces being united to said spaced plates and yielding means for securing said spaced plates to each other.

10. In an airship comprising a rigid hull having a ring member requiring inner bracing, inner braces fixedly secured at their outer ends to the ring member, a plurality of spaced members, the inner ends of said braces being united to said spaced members, and yieldable members connecting said spaced members.

11. A supporting ring for a rigid airship hull having inner braces secured at their outer ends to the ring, a plurality of spaced plates connected to the inner ends of said braces, and means yieldably securing said spaced plates to each other.

12. A supporting ring for a rigid airship hull having inner braces secured at their outer ends to the ring member, spaced members, the inner ends of said braces being connected to said spaced members, and yieldable members connecting said spaced members together.

.LUDWIG DI'JRR. 

